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US4873435A Expired / Lapsed US ⏱️ 0.0 years remaining

Laser beam scanning system

Assignee: Fujifilm Holdings Corp
•
Filing: 1988-01-27
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Granted: 1989-10-10
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Expires: 2008-01-27
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Abstract

Abstract A laser beam emitted from a laser source is deflected by a light deflector such as a rotational polygonal mirror or a galvanometer mirror to scan a surface-to-be-scanned. A beam position detector detects the incident position of the laser beam on the light deflector, and a control circuit drives an optical path changing mechanism according to the output of the beam position detector to change the optical path of the laser beam upstream of the light deflector so that the laser beam impinges upon the light deflector at the regular position.

Inventors

  • 👤 Shuji Ono
  • 👤 Masafumi Yamamoto

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 11:15
CPC Classifications
H; H04; H04N; H04N1/00; H04N1/04; H04N1/047; H04N1/053; G; G06; G06K; G06K15/00; G06K15/02; G06K15/12; G06K15/1204; G06K15/1219; H04N1/113; H04N1/1135; H04N1/12; H04N2201/00; H04N2201/024; H04N2201/02406; H04N2201/02439; H04N2201/02443; H04N2201/04; H04N2201/047; H04N2201/04701; H04N2201/0471; H04N2201/04713; H04N2201/04734; H04N2201/04744; H04N2201/04753; H04N2201/04758; H04N2201/0476; H04N2201/04763; H04N2201/04794; H04N2201/04798

Claims Analysis

Total Claims: 6
Claim 1
Independent Claim 138 words
A laser beam scanning system comprising: a laser source for emanating a laser beam; a light deflector for deflecting the laser beam emanating from the laser source to cause the laser beam to scan a surface-to-be-scanned; an optical wobbling correction means including an optical system by which the laser beam impinges on a light reflection surface of said light deflector as a linear image which is perpendicular to a rotational axis of said light detector, and an afocal optical system by which said light reflection surface of said light deflector and the surface-to-be-scanned are placed in an optically conjugate relationship; a beam position detecting means which detects the incident position of the laser beam on the light deflector; an optical path changing means which changes the optical path of the laser beam upstream of the light deflector; and
Claim 2
Dependent Claim 138 words
A laser beam scanning system comprising: a laser source for emanating a laser beam; a light deflector for deflecting the laser beam emanating from the laser source to cause the laser beam to scan a surface-to-be-scanned; an optical wobbling correction means including an optical system by which the laser beam impinges on a light reflection surface of said light deflector as a linear image which is perpendicular to a rotational axis of said light detector, and an afocal optical system by which said light reflection surface of said light deflector and the surface-to-be-scanned are placed in an optically conjugate relationship; a beam position detecting means which detects the incident position of the laser beam on the light deflector; an optical path changing means which changes the optical path of the laser beam upstream of the light deflector; and
Claim 3
Dependent Claim 34 words
a control circuit which drives the optical path changing means according to the output of the beam position detecting means so that the laser beam impinges upon the light deflector at a predetermined position.
Claim 4
Dependent Claim 34 words
a control circuit which drives the optical path changing means according to the output of the beam position detecting means so that the laser beam impinges upon the light deflector at a predetermined position.
Claim 5
Dependent Claim 142 words
A laser beam scanning system comprising a laser source for emanating a laser beam, a light deflector for deflecting the laser beam emanating from the laser source to cause the laser beam to scan a surface-to-be-scanned, a beam position detecting means which detects the incident position of the laser beam on the light deflector, an optical path changing means which changes the optical path of the laser beam upstream of the light deflector, and a control circuit which drives the optical path changing means according to the output of the beam position detecting means so that the laser beam impinges upon the light deflector at a predetermined position, wherein said light deflector comprises a galvanometer mirror formed of a half-silvered mirror and said beam position detecting means is disposed on the optical path of the light beam passing through the galvanometer mirror.
Claim 6
Dependent Claim 142 words
A laser beam scanning system comprising a laser source for emanating a laser beam, a light deflector for deflecting the laser beam emanating from the laser source to cause the laser beam to scan a surface-to-be-scanned, a beam position detecting means which detects the incident position of the laser beam on the light deflector, an optical path changing means which changes the optical path of the laser beam upstream of the light deflector, and a control circuit which drives the optical path changing means according to the output of the beam position detecting means so that the laser beam impinges upon the light deflector at a predetermined position, wherein said light deflector comprises a galvanometer mirror formed of a half-silvered mirror and said beam position detecting means is disposed on the optical path of the light beam passing through the galvanometer mirror.

References Cited (Backward Citations)

US4143403A Cited
US4314154A Cited
US4404596A Cited
US4441126A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-10-09 1993-04-10 1993-10-10 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-10-09 1997-04-10 1997-10-10 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-10-09 2001-04-10 2001-10-10 $7700.00 Window Closed / Lapsed

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